1. Technical Field
The present invention relates to a tunable interference filter that acquires a light having a specific wavelength, an optical module, and a photometric analyzer.
2. Related Art
In related art, a tunable interference filter (optical filter device) that extracts a light having a specific wavelength from lights having plural wavelengths has been known (for example, see Patent Document 1 (JP-A-2007-86517)).
The tunable interference filter (tunable filter) disclosed in Patent Document 1 has a movable part being opposed to a substrate, displaceable in its thickness direction, and provided with a movable reflection film, plural drive electrodes and detection electrodes provided on the substrate, and a fixed reflection film provided on the substrate and opposed to the movable reflection film. The substrate has two placement surfaces in different locations in its thickness direction. Of the two placement surfaces, the drive electrodes are provided on one placement surface and the detection electrodes are provided on the other placement surface.
In the tunable interference filter disclosed in Patent Document 1, for detection of capacitances between the detection electrodes and the movable part, it is necessary to perform wiring work on the respectively different substrates for lead wires extending from the detection electrodes and the movable part. Accordingly, when the tunable interference filter is incorporated into a module and the wires are connected, there is a problem that the wiring work is complicated.